With all the contraception available to women today, how do you know which is right for you? And what do older women need to know about avoiding pregnancy? A top doctor answers common questions about birth control, including oral contraceptive pills, intrauterine devices and spermicides...

To prevent an unplanned pregnancy, women today have many forms of birth control from which to choose, including prescription methods such as oral contraceptive pills, injections and vaginal ring; over-the-counter choices such as condoms, spermicides and the sponge, as well as permanent methods like tubal ligation.

Even so, “50% of the pregnancies in this country are unplanned,” says Lauren Streicher, M.D., assistant clinical professor of obstetrics and gynecology at Northwestern University’s Feinberg School of Medicine.

“In fact, more than half occur in women over age 40 – the ones who desperately don’t want them.

In roughly half of [all] cases, the woman was using birth control, but either incorrectly or the contraception failed,” she says.

That’s why if you’re of childbearing age, single or newly divorced and sexually active, you need to be knowledgeable about the types of contraception available.

Which are best for you? Read on as Dr. Streicher discusses new developments in birth control, as well as common myths.

What are the biggest myths that women have about the various types of contraception? The topic that comes up most often is that it’s somehow dangerous to take birth control pills that reduce the number of periods you have or stop them altogether.

What are the benefits of using extended cycle oral contraceptive pills, which stop menstrual cycles? There are several. For example, when you eliminate withdrawal bleeding by cutting out the week a woman takes a placebo, then [she] doesn’t have to cope with medical conditions due to hormonal shifts that come with periods, such as PMS [premenstrual syndrome], hormonal headaches or endometriosis.

You also reduce the risk of an unintended pregnancy. If you don’t have those seven days off [the pill], there’s less risk that you’ll start a new pill pack later than you should or mistakenly miss a one.

What side effects occur with extended-cycle pills?Some women have spotting in the beginning. But after three or four months, it goes away.

Some continue to have problems with breakthrough bleeding, but that can happen with standard birth control pills as well.

With standard birth control pills, it’s often simply a matter of trying a different brand of pill.

Is it safe to take the pill if you’re over age 35?If you’re a nonsmoking woman and not at high risk for cardiovascular disease because of obesity or other risk factors, then it’s perfectly fine.

Many women are scared of oral contraceptives because of the Women’s Health Initiative study, which showed that hormone replacement therapy (HRT) increases the risk of breast cancer, heart attack, stroke and blood clots. What do you tell them?Comparing birth control pills to hormone replacement therapy is like comparing apples and oranges.

Hormones act differently in a 35-year-old woman [than] a woman in menopause. The hormones in birth control pills work by shutting down the woman’s natural cycle and, in effect, taking over for them.

Birth control pills have been studied for decades and are extremely safe for most women.

One of the types of contraception, intrauterine devices (IUD), is thought by many to be unsafe. Is that true? The IUD is the most misunderstood and most underutilized of [contraceptive methods] in the U.S. [They’re] widely used in Europe.

In a 2003 Gallup survey of OB-GYNs, more than a quarter said the IUD would be their choice if they didn’t want any more children.

Who is the IUD best for?A lot more women are candidates for the IUD than previously thought.

We used to believe that if a woman never had a baby or she had a prior ectopic pregnancy, then she couldn’t use an IUD. Now we know from experience the IUD is a safe choice for these women.

Why do so many women fear intrauterine devices?Many remember an older IUD called the Dalkon Shield, which was taken off the market because it increased a woman’s risk of developing pelvic inflammatory disease (PID).

The Dalkon Shield’s main problem was that the string that protruded out of the uterus was made of a braided material that acted like a ladder for bacteria to travel up into the uterus from the vagina. So if a woman was exposed to sexually transmitted diseases such as gonorrhea or chlamydia, they were at an increased risk of pelvic inflammatory disease.

Today, the string on IUDs is made of a very fine monofilament that bacteria can’t stick to.

Are there benefits to the IUD over other types of contraception?Unlike the pill or condoms, the IUD doesn’t depend on the user to do or take something correctly.

Of the two types of IUDs on the market, hormonal or copper, which is better?The hormonal IUD is far superior to the copper. The high levels of progestin in the hormonal IUD cause the cervical mucus to become very thick, preventing sperm, as well as bacteria like gonorrhea and chlamydia, from getting through.

Statistically, there’s no increased risk of pelvic inflammatory disease with the hormonal IUD, and in fact, it may even decrease the risk.

The hormonal IUD also has some non-contraceptive benefits, such as eliminating painful and heavy periods. It’s even being studied in the treatment of early uterine cancers as an alternative to a hysterectomy.

The only advantage to the copper IUD is that it can be left in place for 10 years; the hormonal IUD needs to be replaced after five years.

What’s your opinion about the vaginal ring, which a woman inserts into her vagina and replaces at the end of each month?It’s a great choice for some. I have patients who are thrilled with it and are never going back to the pill.

But you need to be comfortable inserting and taking out the ring. Women who are fine with using tampons usually have no issues using the ring.

What do you say to women who prefer natural family planning methods such as fertility awareness?If a patient tells me she wants to use that form of birth control, I tell her there’s a very high failure rate and her chances of getting pregnant are fairly high.

Of the many barrier types of contraception, is the diaphragm a good option?It’s rare that a patient asks for this form of birth control. But some women prefer it, and it’s certainly as good as condoms at preventing pregnancy.

The other product that I rarely hear about is the female condom, which is a reasonable method for women concerned about STD protection and their partners [who] refuse to wear condoms.

Do you recommend over-the-counter spermicides?Yes – as long as they’re used correctly and every time you have sex.

In fact, the combination of condoms with spermicides has an extremely low failure rate.

If you use spermicides correctly, you [won’t] get pregnant – even if the condom breaks or comes off.

What options do women have if they have unprotected sex and are worried about an unplanned pregnancy?Many women don’t realize that emergency contraception is now available over-the-counter.

Ideally, you should use it within the first 72 hours after unprotected intercourse, but it can be used up to five days afterward.

The rules vary from state to state [about] how old you have to beto buy it, so it’s stored behind the counter.

In some states, you need to be over 21.

But Planned Parenthood’s website, BC4U.org, has instructions for women who want to have an emergency contraception prescription phoned in to a local pharmacy.

Does birth control become less important once a woman reaches her 40s, since her chances of conceiving are pretty low?This is another common misconception.

They get relaxed about contraception, but if you’re still regularly menstruating, then you can get pregnant.

At age 44 or 45, your chances of having a viable pregnancy are pretty low.

Women who conceive at that age have a very high chance of miscarrying.

What else do older women need to know types of contraception?Women in their 40s and 50s who are divorced or widowed and back on the dating scene need to be diligent about safe sex.

The divorce rate today is 50%, [and] you have an entire population of women over the age of 40 and 50 out there dating.

And the men they’re sleeping with are not virgins.

I deal with a lot of older patients who were monogamous throughout their marriages and maybe had two sexual partners their whole lives. [Then] they start dating and end up with HIV or herpes.

In many cases, these women are savvy about sexually transmitted diseases and say they fully intended to use a condom, but the man refuses.

Are older women candidates for the HPV vaccine that’s currently recommended for teenagers?The vaccine is not FDA-approved for this age group, but doctors are free to give it to these patients “off label,” and I regularly offer it to my patients.

Insurance won’t pay for it, but many of my patients are OK with paying the full cost themselves.

Women's Health: How Much Do You Know?As a woman, your health concerns are as unique as your body. How you take care of yourself has a huge impact on your future, affecting everything from your ability to have children to your risk of heart disease. There's no substitute for good health, and when it's gone, it's often gone for good. Don't let it pass you by. Test your smarts with this women's health quiz.

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